Flash and Elongated Man are busy fighting the Thinker until it is revealed that it was just a training simulation. The two heroes are not agreeing on how to handle the DeVoe situation as Ralph is still a target.
The team is busy looking for the remaining bus-metas, but Harry is struggling with the Thinking Cap. Breacher suddenly appears from Earth-19 and tells Team Flash that he needs help as a villain named Crucifer is after him.
DeVoe, in his latest stolen body, is beginning to feel ill as he is going to need to move his mind again. Marlize insists to let her help DeVoe find a different solution, but DeVoe insists on finding the final bus-metas.
The next bus-meta Null is busy stealing a crown. The next day, Barry and Ralph help Joe investigate what happened. Back at Star Labs, Cisco tries to help Breacher with his problem.
When Breacher leaves the room, Caitlin tells Cisco that it wasn't Crucifer that stole his powers. It is Breacher's aging that is causing the problem.
Marlize discovers the mystery liquid back at DeVoe's lair and begins to analyze what it is. Back at Star Labs, they locate Janet Petty as Ralph, disguised as Joe, with Barry, goes to interrogate Ralph's former partner.
Janet was working with him the whole time and gets Barry to float. They take him back to Star Labs as they try to figure out how to reserve this.
Harry says that it will wear off, followed by Barry dropping down. Barry gets angry with Ralph and asks why he pulled that stunt.
Marlize runs tests on herself to see what is going on with her. She begins to realize what Clifford has been up to.
Cisco and Caitlin try to find a cure to help Breacher, but they are struggling. He gets Breacher to take a pill and somehow his powers work.
Harry comes up with a plan for Flash to go after Null without being affected by her powers. Barry rushes off and cuffs her, but sees that she got a car to float with the driver still inside.
The Flash runs up in the air to save the driver and gets him down to safety. Unfortunately, Null has already escaped.
Cisco goes to see Breacher, but sees that he has taken off already and vibes that he is confronting Crucifer. Vibe joins him and takes out Crucifer.
They return to Earth-1 where Cisco admits to Breacher that his powers are fading. Marlize is saving a recording of herself of what she learned, but discovers that she has recorded several videos already,
DeVoe confronts her and admits that this scenario has happened several times, Marlize tries to go up against him, but Clifford drugs her again.
Barry goes to talk with Ralph and get to the seed of why Ralph jokes around so much. Ralph tells him how his father walked out on him when he was 10 and why he behaves the way he does.
They are alarmed about Null going after a fundraiser and takes off. The Flash and Elongated Man get to the fundraiser to stop Null.
Null manages to get Flash to float again as Barry tells Ralph to improvise. Ralph stops Null and manages to save Barry as he falls back down to the ground.
Breacher returns to Cisco and tells him that he is retiring. He also offers Cisco to take over for him on Earth-19 so he can be more with Cynthia.
Marlize returns to assist DeVoe once again as she has no recollection of what happened. In a post-credits scene, Harry goes to Eobard's Time Vault to charge the Thinking Cap.
He also accidentally reactivates Gideon.